Esterification on solid support by surface‐initiated ring‐opening polymerization of ε‐caprolactone from benzylic hydroxyl‐functionalized Wang resin bead

Abstract

AbstractBiodegradable poly(ε‐caprolactone) (PCL) was formed on benzylic hydroxyl‐functionalized Wang resin surface by surface‐initiated ring‐opening polymerization (SI‐ROP). The SI‐ROP of ε‐caprolactone was achieved first by treating Wang resin with Tin(II) 2‐ethylhexanoate [Sn(Oct)2] to form Tin(II) complex, and then followed by polymerization of ε‐caprolactone in anhydrous toluene at 60°C. Thus, the polymer‐grafted Wang resin was characterized by Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), optical microscopy (OM), and field‐emission scanning electron microscopy (FE‐SEM). The FTIR spectroscopic analysis of polymer‐grafted Wang resin (Wang‐g‐PCL) reveals the formation of ester linkage between PCL and hydroxyl‐terminated Wang resin. The DSC thermogram shows melting peak corresponding to PCL polymer on Wang resin surface. Thermogravimetric investigation shows increase in PCL content on the Wang resin surface in terms of percentage of weight loss with increase in reaction time. The formation of polymeric layers on the Wang resin surface can be directly visualized from OM and SEM images. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009